High Output alternator .. fuse replacement ?

[Rob. 10+ year member]

Hi guys, Im gonna be installing my 170 amp alt in my 1990 civic si.

My stock alt is 60 amp with a fuse of 60.

Is it necessary to change the fuse with a higher 170 amp fuse in the fusebox? ?

heres a reference pic of a civic underhood fusebox. Which one do I replace ?

Click to read more...

 

[PaulThompson229 10+ year member]

No fuses need be replaced, run a 1/0 cable from the alts charging post directly to the batterys pos post (as in doing the big 3) and fuse that wire to its max amperage handling (normally 300A for 1/0)

 

[Rob. 10+ year member]

wouldnt it be easier just to change the fuse in the fusebox ?

Im only gonna be running 1 4 channel amp.

 

[PaulThompson229 10+ year member]

Your stock wiring will not hold up to 170 amps, you need at least 2 gauge.

 

[Rob. 10+ year member]

Your stock wiring will not hold up to 170 amps, you need at least 2 gauge.

I was told 4 guage is fine for 170 amps.

Im still a lil confused.

If I run a new 0guage or 2 guage wire to my positive battery post from the alt, what happens to my old wiring and fuse ?

 

[SWFL 10+ year member]

its fine leave stock and just run new wire or disconnect the old if u are worried

 

[PaulThompson229 10+ year member]

I was told 4 guage is fine for 170 amps.Im still a lil confused.

If I run a new 0guage or 2 guage wire to my positive battery post from the alt, what happens to my old wiring and fuse ?

4 gauge is only good for up to 150A, and leave all the stock stuff alone, just add on to it.

 

[Rob. 10+ year member]

Isnt it easier to run new 2 guage wiring from the alt to the battery post and add a new 170 amp fusible link in the fusebox ?

 

[PaulThompson229 10+ year member]

If you run the new wire there will be no need to change anything in the fusebox, plus I dont even think they make fuses that large in that style.

 

[Rob. 10+ year member]

hmm.. ok..

so I should just replace the stock alt wire to the battery + post, with a new 2 guage wire and fuse ?

 

[Pioneer~Saturn 5,000+ posts]

Run 1/0 gauge..isnt much more money and get an ANL fuse holder inline with it with a 200 amp fuse in it and go to town..